The answer is "Option C".
Step-by-step explanation:
Robust standard errors or generic White-Huber mistakes depending on this procedure. This is also recognized as the Variance Sandwich Stimator because of the appearance of the formula. Therefore, which is under homoskedasticity, robust error terms were appropriate, in which the standard deviations of its predictor variables are non-constant and are tracked across different values or linked to pre-time periods of an exponential function.